Gravity Kits, what are the benefits?

[pocono53]

I'm in the process of deciding between the Pacific Energy FP30 Arch or the Osburn Stratford and I wanted to know what how useful the gravity kits will actually be. I had a few questions considering both fireplaces have blowers and louvers just above the firebox... I am trying to heat a vacation cabin and want to make sure I'd be able to do so if the electric goes out...and I don't want a stove.

1. Do you need to close off the louvers in order to make the gravity vents work? Once closed off the fans pump the airs thru the vents right?
2. In the event the power goes out, how much heat can I expect to come out of the gravity vents? Would this be better that if I just used the louver vents above the firebox?
3. Can I leave the louvers above the firebox open and have the fan push the air out of the louvers and the gravity vents?

I'm hard time making this decision (buying gravity vents) and finding a ton of info on the FP30 is hard when considering gravity vents. What would you guys suggest? Nobody around here has either of these as floor models and since they are newer the salesmen don't know as much.

Any advice would be greatly appreciated!

 

[begreen]

If the cabin floor plan is open then there may be no need for the gravity vents. Good operation with them depends on the layout of the house and routing of the ducting from the vents.

 

[pocono53]

Thanks for the response. I was just going to duct them out into the same room above the mantle. How much air comes out of the gravity vents if the fan isn't on?

 

[bfast250]

The FP30 has a remote heat duct kit which includes an outlet blower. Are you looking to install gravity vents using the heat duct adapter without fans?

I am interested in this fireplace as well and the use of the gravity vents without the outlet blowers. Like you I question the value of this configuration.

 

[pocono53]

I'm not interested in the remote heat duct kit with the blower.

I'm looking for info on just installing the regular gravity vents, how good the work and how they work with the blower thats for the firebox. Basically the question is should I get the gravity kit because they pump out heat/air whether the blower is on or off.

Looking for advice and info

 

[begreen]

Thanks for the response. I was just going to duct them out into the same room above the mantle. How much air comes out of the gravity vents if the fan isn't on?

I haven't had the opportunity to see this fireplace in operation with the gravity vents. If they work like other units I think one can expect a decent amount of heat coming out of the vents if properly installed. Have you contacted Pacific Energy with this question? @thechimneysweep do you have any thoughts on the effectiveness of the gravity kit option on the FP30?

 

[xman23]

What's a gravity vent? I'm just trying to envision the heat from my stove being influenced by the gravitational pull of the earth.

 

[begreen]

It's a misnomer. Convective vent would be a better name.

 

[Mike M.]

I might be wrong but doesn't the arched FP30 have a larger vent above the firebox? I have the square version and 2 gravity (convection) ducts. If I could start over there would be no gravity vents in my house. They are ugly. This unit will not heat with out power. Consider a generator or DC battery / inverter.

Sent from my SM-G920R6 using Tapatalk

 

[bfast250]

Your thread (https://www.hearth.com/talk/threads/pe-fp-30-gravity-vent-ideas.143214/) is what inspired me to look into the gravity vents. In my case I would like to place the vents behind the fireplace to help provide heat to that area.

What kind of heat do you get out of the vents? Does the airflow from the gravity vents change if the fireplace blower is on/off? Did you install any air inlets for the cavity surrounding your fireplace? Thanks in advance for your input!

 

[Mike M.]

The operation is the following- if the fan is on all the heat (air) comes out above the firebox. If the fan is off, the gravity ducts work. There is an air intake on the lower right backside that I have piped in. The best thing I did is apply a variable speed control to the fan. Just looked back at the thread mentioned. My TV is now above the FP30 (it hides the gravity vents which I never use).

Sent from my SM-G920R6 using Tapatalk

 

[begreen]

I would think that gravity vents would be most effective in an installation where either there is a floor above needing heat or the fireplace is against an interior wall and one wants to heat the other side of the dividing wall. If the fireplace is built into the room the vents could be placed on the sides to be less conspicuous.

 

[Mike M.]

I do not want to sound negative, this is a good stove. The unit heats well with the fan and has an awesome view of the fire. My wife really likes the stove and wants me to burn it all the time in the winter which is a bonus. The fire is super easy to start and burns cleanly down to nothing but fine ash. Other than the gravity vents being somewhat useless in my application my only other complaint would be the cold air that enters the house just below the ash lip of the stove.

 

[pocono53]

I do not want to sound negative, this is a good stove. The unit heats well with the fan and has an awesome view of the fire. My wife really likes the stove and wants me to burn it all the time in the winter which is a bonus. The fire is super easy to start and burns cleanly down to nothing but fine ash. Other than the gravity vents being somewhat useless in my application my only other complaint would be the cold air that enters the house just below the ash lip of the stove.

How is cold air getting in under the ash lip? I would assume you installed the cold air intake...which would not let this happen?

 

[Tech Guru]

keep in mind that the FP30 'A' original version used a gravity vent option. The newer, current 'B' version uses the powered remote heat duct.

 

[Mike M.]

How is cold air getting in under the ash lip? I would assume you installed the cold air intake...which would not let this happen?

Yes I have the outside air intake. Cold air comes out by the burn control lever located just under the ash lip. It even causes condensation (almost frost) on the unit in extreme cold. I am debating on plugging the outside air vent and trying the until since it is not an air tight setup.

Sent from my SM-G920R6 using Tapatalk

 

[bfast250]

keep in mind that the FP30 'A' original version used a gravity vent option. The newer, current 'B' version uses the powered remote heat duct.

The current 'B' version still has the gravity heat duct adapter listed as a replacement part:
*23 ........Gravity Heat Duct Adapter...................... FP30.9128

 

[pocono53]

So gravity vents are not included in a new version....they are now powered?

 

[Tech Guru]

That is correct, the newer versions of the unit were brought to market well over a year ago, so I would figure unless the dealer or distributor has some older existing stock of the 'A' version, you may only have the powered (fan assisted) version of the remote heat transfer kits. The certification issue being the old units were only tested/listed with the gravity kits, and the current 'B' model was only tested with the powered versions.

 

[bfast250]

That is correct, the newer versions of the unit were brought to market well over a year ago, so I would figure unless the dealer or distributor has some older existing stock of the 'A' version, you may only have the powered (fan assisted) version of the remote heat transfer kits. The certification issue being the old units were only tested/listed with the gravity kits, and the current 'B' model was only tested with the powered versions.

I have a request in to Pacific Energy regarding the use of gravity vents on the 'B' version. I will let you all know when I get a response.

 

[xman23]

It's a misnomer. Convective vent would be a better name.

Duh, I get the similarity now.

 

[bfast250]

Following up like I said I would. I received a response from PE yesterday.

I asked the following questions:

I am interested in an FP30AR series B zero clearance wood fireplace. I would like to install vents in my chase to allow heat out of the back of the chase which is still interior to the home. I am not interested in blowers. Can the heat duct adapter (part number FP30.9128) be used with class B venting (part number 5095.7) without the remote duct kit/blower on the FP30AR series B?


Is the FP30AR series B designed to allow heat out of the heat duct openings and the front of the fireplace? How will the use of the fireplace blower affect the heat coming out of the heat duct openings?

And here is the response from PE:

The FP30AR B series is not designed for use with a gravity style heat take off as you proposed. It was tested with the WODC.RHKA powered heat take off kit and must be used as designed. Modifying the system would void your home insurance in the event of something going wrong.

You can place non- ducted vents into the rear of the chase, I would suggest placing an equivalent size opening near the bottom of the chase to promote flow.

The installed convection blower does blow heated air up the rear of the firebox, across the top and out the front grill area. The remote heat duct openings are in a separate chamber from the convection fan system.